Divestitures (Condensed Cash Flow Statement) (Details) - USD ($) $ in Millions		12 Months Ended
		Aug. 01, 2021	Aug. 02, 2020	Jul. 28, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Disposal Group, Including Discontinued Operation, Depreciation and Amortization	[1]		$ 0	$ 83
Net (gain) loss on sales of discontinued operations businesses			(1,039)	(32)
Payments to Acquire Property, Plant, and Equipment		$ 275	299	384
Proceeds from Divestiture of Businesses, Net of Cash Divested		101	2,537	539
Asset Impairment Accelerated Depreciation [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued Operations, Impairment charges			0	377
Discontinued Operations, Held-for-sale or Disposed of by Sale [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Payments to Acquire Property, Plant, and Equipment		$ 0	30	59
Proceeds from Divestiture of Businesses, Net of Cash Divested			$ 2,466	$ 539

[1] Depreciation and amortization are no longer recognized once businesses are classified as held for sale/discontinued operations.